Bioremoval of Graffiti in the Context of Current Biocleaning Research

Some microorganisms can be used as bioremediation agents, in biocleaning treatments, to remove undesired sulphates, nitrates and organic matter from cultural heritage surfaces. Graffiti materials (mainly spray paints) are now included in the list of materials that can be biocleaned, with studies on this topic being initiated just over 5 years ago. Research on the bioremoval of graffiti is continuing and on a promising track. This chapter reports a critical analysis of studies of the bioremoval of graffiti carried out in recent years, which are compared with similar studies of the removal of salts (mainly nitrates and sulphates) and organic matter conducted in the last thirty years. Likewise, the present challenges and ways of overcoming them are addressed towards developing a complete protocol for the use of bioremediation to remove graffiti, with particular emphasis on the use of the method for cleaning facades and buildings.